In that case what is the temp probe at the output of the HLT HERMS coil for?

I used to have my MLT temp probe there but found that it always followed the HLT water temp from the temp probe on the output of my HLT exactly. It was redundant. Something to keep in mind as yours might behave the same way if your HERMS coil is big/efficient enough. The temp of the wort coming out of the HERMS coil in my case was always equal to the HLT water temp.

So I moved my MLT temp probe to the output of the MLT so that I could monitor how fast my MLT rose in temperare compared to the HLT when I did step mashes and mash-out. (This is the way I describe my build on my site today - I never actually had it documented with the MLT temp probe on the output of the HERMS coil as I made the change before I started documenting).

In that case what is the temp probe at the output of the HLT HERMS coil for?

I used to have my MLT temp probe there but found that it always followed the HLT water temp from the temp probe on the output of my HLT exactly. It was redundant. Something to keep in mind as yours might behave the same way if your HERMS coil is big/efficient enough. The temp of the wort coming out of the HERMS coil in my case was always equal to the HLT water temp.

So I moved my MLT temp probe to the output of the MLT so that I could monitor how fast my MLT rose in temperare compared to the HLT when I did step mashes and mash-out. (This is the way I describe my build on my site today - I never actually had it documented with the MLT temp probe on the output of the HERMS coil as I made the change before I started documenting).

Kal

The temp probe at the output of the HLT HERMs coil was to measure the MLT temp. So your saying I should move that to my output on my MLT.

I'm saying that with my setup a temp probe there always measured the same as my HLT probe at the HLT output so it was redundant. You may want to try it there but then consider moving it to the MLT output if the same happens to you. Depends on how efficient your HERMS coil is at transferring heat.

Measuring how fast the entire mash bed (the MLT output temp) is raising in temperature is IMHO more important than measuring the output of the bit of wort coming out of the HERMS coil. That doesn't tell you what your mash is doing.

I'm saying that with my setup a temp probe there always measured the same as my HLT probe at the HLT output so it was redundant. You may want to try it there but then consider moving it to the MLT output if the same happens to you. Depends on how efficient your HERMS coil is at transferring heat.

Measuring how fast the entire mash bed (the MLT output temp) is raising in temperature is IMHO more important than measuring the output of the bit of wort coming out of the HERMS coil. That doesn't tell you what your mash is doing.

Yup, make sense. I did the both ways too because I first wanted to confirm that my HERMS coil was transferring heat efficiently. I did 4-5 batches and on all of them my two PIDs (HLT and MLT) always displayed the exact same temperature (this is with both probes calibrated correctly of course).

So I moved it the MLT probe to the MLT output. Now I see how a larger mash (like a barley wine) takes twice as long to go to mash out as a light lager that uses 1/3 the grain.

I finally got my electrical issue solved. I had an electrician install a 100A sub panel with a 50A breaker that feeds my new 240v line that is attached to a 50A 4-prong receptacle. I made a separate thread about it, so if your interested in looking at it, here's the link http://www.homebrewtalk.com/f170/the...l-like-360443/

Trying to decide on a HERMs coil. All my kettles are going to be made out of kegs, and I can't decide on the diameter and length. Kal's notes say to have the coil be 50' of 1/2" OD at 11.25" in diameter and 9" high. I would like to get my HERMs coil from Stainless Brewing, but the diameter they offer for 50' 1/2" OD is 10" or 12". Should I just go with the 12"?